Homework $7-$ Encapsulating Node with GPTree

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It$$s time to plan ahead for the Genetic Programming project. If we try to process more trees in our main$()$ method, it will get unwieldy and hard to maintain. A simplistic rule of thumb is that main$()$ shouldn$$t have more than about $20$ lines of code in it$.$ It should make a few objects, and then tell them to $"$go about their business."

Starting Out:

Copy the files from your completed Refactoring project to this directory

After you copy the files, only two of the copied files should be modified

Node.java $-$ to add concrete methods traverse$(),$ swapLeft$($Node trunk$),$swapRight$($Node trunk$),$ and isLeaf$().$

Divide.java $-$ to fix division by zero.

The task

One way to add useful encapsulation is to create a GPTree class that consolidates some of the functionality of trees. Currently, the Node class knows how to do things, but a tree class that encapsulates the root node of a tree will be useful. This process has five steps.

Step $1$ The Node class will be modified to have a traverse$($Collector c$)$ method that will recursively give Nodes in the Tree to the Collector interface to collect them. That way, a list of potential binary Nodes will be held by the GPTree to be randomly selected as crossover points.

Step $2$ You will add $3$ new files to this project, Collector.java, GPTree.java and TestGPTree.java described below.